Suction nozzle



Dec. 19, 1961 R. DESCARRIES 3,013,295

SUCTION NOZZLE Filed May 26. 1959 3 Sheets-Sheet 1 {Adam k; ATIU/PA/KKDec 19, 1961 R. DESCARRIES 3,013,295

SUCTION NOZZLE Filed May 26. 1959 3 Sheets-Sheet 2 FIG. 5

INVENTOR.

Dec. 19, 1961 R. DESCARRIES 3,013,295

SUCTION NOZZLE Filed May 26, 1959 3 Sheets-Sheet 3 INVENTOR.

fZ/ A! Arron/0.

Patented Dec. 19, 1961 3,013,295 SUCTION NGZZLE Raymond Desearries,Montreal, Quebec, Canada, as-

signor to Aktiebolaget Eiectrolux, Stockholm, Sweden, a corporation ofSweden Filed May 26, 1959, er. No. 815,844 8 Claims. (Cl. 15-417) Thisinvention relates to suction cleaner nozzles and particularly tomultiple purpose nozzles suitable for cleaning surfaces of differentcharacters.

Devices of this general type comprise a nozzle body having at least twoworking faces, one of which may, for example, be provided with a brushfor engagement with a floor or like surface, and the other with smoothportions for engagement with rugs or the like, passage means beingprovided to lead air from each work face to a common outlet whichcommunicates with the suction cleaner fan. Usually, the nozzle isattached to one end of a rigid tube or wand, the other end of which isconnected to a length of flexible hose leading to the inlet of the fanchamber, and the nozzle is manipulated manually by means of the wand.Since each working face must be capable of being brought iutopositionfor engagement with the surface being cleaned, the nozzle is mounted onthe wand in adjustable fashion. Since it is desirable to have all of theair flowing to the suction cleaner fan pass via the working face whichis in use, some form of adjustable valving must be employed.

An object of the present invention is to provide a suction cleanernozzle of the type referred to so constructed that all of the requiredadjustments of the nozzle and its valve means can be accomplished in avery simple manner by manipulation of the tube or wand to which thenozzle is attached.

Another object is to devise a multiple purpose suction cleaner nozzleadapted to be rotatably attached to one end of a manipulating tube orwand and embodying valve means operable simply by application of aslight pressure to the tube or wand when the desired working face of thenozzle is in engagement with the surface to be cleaned.

A further object is to provide an improved, highly simplified valvearrangement for multiple purpose suction cleaner nozzles.

Yet another object is to provide a multiple purpose suction cleanernozzle including oscillatory valve means comprising only a singlemovable part.

in order that the manner inwhich these and other objects are attained inaccordance with the invention can be understood in detail, reference ishad to the accompanying drawings, which form a part of thisspecification, and wherein:

FIG. 1 is a perspective view of a suction cleaner nozzle constructed inaccordance with one embodiment of the invention;

FIG. 2 is a sectional view taken on line 22, FIG. 1, illustrating theparts in the same position as in FIG. 1;

FIG. 3 is a sectional view similar to FIG. 2, but illustrating the mainnozzle body in inverted position as compared to FIG. 2;

FIG. 4 is a sectional view similar to FIG. '3 but showing certainelements of the device in a second position;

FIG. 5 is a sectional view taken on line 5-5, FIG. 2;

PEG. 6 is a plan View of one main nozzle body member of the device ofFIG. 1, viewing that member as indicated by line 6-6, FIG. 2;

FIG. 7 is a plan view of the other main nozzle body member of the deviceof FIG. 1, viewing the member as indicated by line 77, FIG. 4;

FIG. 8 is an exploded perspective view of a spring detent employed inthe device of FIG. 1, and 7 FIG. 9 is a perspective View of acombination movable valve member and nozzle outlet connector forming apart of the device of FIG. 1.

Referring now to the drawings in detail, and first to FIGS. 1, 2 and 5-9thereof, it will be seen that the embodiment of the invention hereillustrated comprises a nozzle body 1 formed by mating members 2 and 3which have flat faces 4 and 5, respectively, the members being securedtogether, as by screws 6, with faces 4 and 5 in contact.

Member 2 is elongated in a direction transverse to the intended path oftravel of the nozzle in use and may thus be said to have a front face 2and a rear face 2*. Opposite face 4, member 2 is provided with anelongated channel 7 extending in the long direction of the member andopening away from face 4, the bottom wall of the channel slopinginwardly to a centrally disposed opening 8 communicating with arearwardly opening air passage 9. Rigid work surface-engaging elements10, of conventional construction, constituting a work face, and suitablefor operative engagement with a rug or the like during use of thenozzle, extend on each side of channel 7.

Member 3 is similar in plan to member 2 and is also provided, oppositeits side 5, with a work face having a centrally disposed opening 12communicating with a rearwardly opening air passage 13. Mounted at thework face of member 3 in any suitable fashion, as by being clamped inchannels 11 and 14, are the usual brushes 15 to be employed when thenozzle is used in cleaning floors and like hard, smooth surfaces.

It will thus be seen that there are two separate and independent workfaces disposed on opposite sides of the body of the nozzle, and that,when the mating body members 2 and 3 are fitted together, there areprovided two substantially L-shaped air passages, the arms 8 and 12 ofwhich extend inwardly from the respective work faces, and the arms 9 and13 of which terminate in rearwardly directed outlet openings. Side walls16 of passage 9 are aligned with side walls 17 of passage 13. The twopassages are separated by a plate on partition 18 dis-posed generally inthe plane of mating faces 4 and 5, the front and side edges of the platebeing disposed in suitable notches in members 2 and 3, as indicated at19 in FIG. 2, and being clamped between members 2 and 3 to secure theplate in a position preventing communication between passages 9 and 13.

Forwardly of the front walls 20 and 21, FIG. 2, of passages 9 and 13,elongated grooves 22 and 23 are respectively provided in faces 4 and 5of members 2 and 3, these grooves extending parallel to walls 20 and 21.Grooves 22 and 23 are so located as to mate when members 2 and 3 aresecured together with faces 4 and 5 in contact. Hence, the groovescombine to provide an elongated-recess extending in the long directionof the nozzle body.

Adjacent each side wall 16 of passage 9, member 2 is provided with aslot 24 extending at right angles to the axis of groove 22, each slot 24intersecting groove 22 and extending to a point forwardly thereof. Asviewed from an end of the nozzle, slots 24 have the general shape of aright triangle.

Adjacent each side wall 17 of passage 13, member 3 is provided with aslot 25 extending at right angles to,

groove 23, each slot 25 intersecting groove 23 and extending to a pointforwardly thereof. Viewed from an end of the nozzle, slots 25 also havethe general form of a right triangle.

When members 2 and 3 are secured together in the fashion shown in FIG.1, each slot 24 registers with a slot 25. Each registered pair of slots24 and 25 thus provides a space disposed at one side of the air passages9 and 13, which space communicates with the recess 3 defined by grooves22 and 23 and opens through the rear face of the nozzle body.

At its rear face 2", member 2 is provided with two pairs of uprightrearwardly projecting webs 26, each pair of webs being spaced apart andso disposed as to define an extension of a different one of slots 24.Similarly, member 3 is provided at its rear face 3 with two pairs ofupright rearwardly projecting webs 27, each pair being spaced apart andso located as to define an extension of a different one of slots 25. Asillustrated in FIGS. 1 and 2, each web 26 combines with a web 27 toprovide an arcuate edge 28 centered on the longitudinal axis of therecess defined by grooves 22 and 23. At their upper ends, the webs 26are joined by an edge portion 29, FIG. 1, on member 2. At their lowerends, webs 27 are joined by a similar edge portion 30, FIG. 2, on member3. Transversely the rear edge 31 of plate 18 extends arcuately in thesame direction as do edges 28, is in alignment with edges 23, and hasthe same radius of curvature as do edges 28. It will be noted that edges23, 29, 36 and 31 define two separate outlet openings, one for each ofthe passages 9 and 13. it can also be said that these edges combine todefine a cylindrical surface the longitudinal axis of which iscoincident with the longitudinal axis of the recess provided by grooves22 and 23.

The nozzle is connected to the usual manipulating tube or wand 32, FIG.2, by means comprising an elbow 33 and a combination connector andmovable valve member, indicated generally at 34-. Member 34 includes ashort tubular portion 35 within which one end portion of elbow 33 istelescopically disposed and arranged for swiveling movement in anysuitable conventional fashion. Member 34 also includes a hollow portion36 of rectangular transverse cross-section and a pair of parallel,spaced supporting arms 37 projecting from the end of portion 36 oppositeelbow 33. The side walls 38 of portion 36 diverge forwardly andoutwardly and each arm 37 extends forwardly from a different side wall38, as illustrated in FIG. 9. At its forward end, each arm 37 isprovided with a transverse bearing opening, the two bearing openingsbeing aligned transversely of the supporting arm, and a plaincylindrical rod or shaft 39 extends through the bearing openings. Rod 39is dimensioned to be clamped within the recess provided by grooves 22and 23 when members 2- and 3 are secured together. Supporting arms 37are of such thickness, and are spaced apart at such a distance, that,when rod 39 is clamped in the recess provided by grooves 22 and 23, eacharm 37 can pivot through a different one of the spaces afforded byaligned slots 24 and 25.

Fortion 36 of the combined connector and movable valve member 33 has aforwardly facing air inlet opening defined by front edge 40 of top wall41, edge 42 of bottom wall 43 and two end portions 44 located each atthe forward end of one of the side walls 38. The edges defining the airinlet opening for portion 36 also define a plain cylindrical surface thelongitudinal axis of which is coincident with the longitudinal axis ofrod 39. it may thus e said that, while the edges defining the outletopenings of passages 9 and 13 define a convex cylindrical surface, theedges defining the inlet opening for portion 36 of the combinedconnector and movable valve member define a cylindrical surface which isconcave and has the same radius of curvature as the cylindrical surfacedefined by the edges of the outlet openings of the air passages. Thus,when rod 39 is disposed in the recess provided by grooves 22 and 23, theedges defining the inlet opening for the member 33 slidably engage edges23 and 31 and can be brought into flush engagement with edge portions 29and 30.

As will be seen in FIG. 2, the height of the outlet opening for passagesg and 13 equals the height of the inlet opening of member 34.Accordingly, if front edge 40 of top wall 41 of portion 36 engages edgeportion 29 of member 2, front edge 42 of bottom wall 43 of portion 36will engage edge 31 of plate 18. Portions 44 will, of course, engageedges 28 of webs 26. With the parts so positioned, the interior ofportion 36, and hence the interior of the wand 32 connected to elbow 33,is in communication with passage 9 and, therefore, with the work face ofmember 2.

On the other hand, if edge 46 of top Wall 41 of portion 36 engages edge31 of plate 18, front edge 42 of bottom wall 43 will engage edge portion39 of member 3 and the wand 32 will be in communication with passage 13and, therefore, with the work face of member 3.

At a point beside but spaced from one slot 24, a semi cylindrical recess45 is provided in face 4 of member 2, recess 45 having its axisextending at right angles to such slot. Recess 45 communicates with theslot via an intermediate channel 46 of rectangular transversecross-section. An identical recess 4-7 is similarly provided in face 5of member 3, recess 47 communicating with the adjacent slot 25 via achannel 48 identical to channel 46. Recesses 45 and 47 are so located asto register when members 2 and 3 are assembled to form the nozzlebody 1. Disposed to reciprocate in the space afforded by recesses 45 and47 and channels 46 and 48 is a rigid detent member 49, the top of whichis normally biased into the junction of the adjacent mating slots 24, 25by a helical compression spring 50.

Detent member 4% has a body 51 of square transverse cross-section, body51 being slidably disposed in the space defined by channels 46 and 48.The tapered tip 52 of the detent body is formed by two slanting surfaces5?. each facing a different one of the mating slots 24 and 25 into whichthe tip projects under the influence of spring 50. Opposite tip 52, thedetent is provided with a circular flange 53 and a cylindrical extension54, the latter being disposed within spring 50. As seen in FIG. 5,spring 50 has one end seated against an end of the space defined byrecesses 45 and 47, the other end of the spring being seated againstflange 53. Hence, the spring is effective to bias flange 53 against theshoulder provided at the junctions of recesses 45, 47 and channels 46,48. When the detent member 49 is in this position, the tapered tip 52thereof projects into the space defined by the adjacent pair of slots24, 25 and thus lies in the path of travel of the corresponding one ofsupporting arms 37.

Supporting arms 37 are each provided, on each edge, with adetent-camming surface 55 extending approximately radially of the axisof rod 39. Each detent member camming surface 55 has a portion disposedto lie in flush engagement with one of the faces 52 when the combinedconnector and movable valve member 34 occupies the appropriate one ofits two extreme pivoted positions, in which position the member 34registers with one or the other of passages 9 and 13. Thus, the detenttends to restrain member 34 in that valving position to which it hasbeen pivoted. Movement of member 34 away from such position withsufiicient force is, however, effective to overcome the biasing actionof spring 50 and force detent member 40 laterally of adjacent slots 24and 25 to an inactive position.

The nozzle construction represented by this embodiment of the inventioncan be assembled very simply by first inserting shaft 39 through thealigned bearing openings in supporting arms 37 of member 34, thendisposing the shaft 39 in one of the grooves 22 or 23, then placingplate 18 in its proper position, and then fitting the two body members 2and 3 together and securing them by means of screws 6.

The manner in which the nozzle is employed, and the simplicity of itsoperation during use, will be clear from FIGS. 2-4. In FIG. 2, thenozzle is shown with brushes 15 engaging a floor F, and with combinationconnector and movable valve member 34 disposed in registry with airpassage 13, in which position member 34 is restrained by detent member49. Elbow 33 is disposed with its free end portion extending upwardly atthe angle at which the user maintains the manipulating tube or Wand 32.

Assuming now that the user wishes to employ the nozzle in cleaning arug, for which purpose work-engaging elements are appropriate andbrushes unsuitable, nozzle body 1 is turned over, so that work elements10 engage the surface of rug R, elbow 33 turning in portion 35 of member34 so that the proper angle of manipulating tube or wand 32 can bemaintained. At this point, member 34 remains in communication with airpassage 13 and therefore with the space between brushes 15. See FIG. 3.A slight downward pressure on the wand 32 is, however, effective toovercome the biasing action of detent spring 50, and such pressuretherefore causes member 34 to pivot downwardly, about the axis of rod39, until the inlet opening of portion 36 thereof registers with theoutlet opening of air passage 9, placing the wand, and thus the suctioncleaner fan, in communication with the proper work. face of the nozzle,as seen in FIG. 4. Hence, the suction cleaner is now effective to drawair from the rug R via channel 7, opening 8, air passage 9, portion 36of member 34,- elbow 33, the wand 32 and the usual flexible hose, andthe rug is cleaned in normal fashion.

When it is again desired to use the nozzle on a smooth,- hard surface,such as a floor, the nozzle is again ro-' tated half a turn about theaxis of portion 35 of member 34, bringing brushes 15 to the positionseen in FIG. 2, and slight pressure is again applied to the wand 32 topivot member 34 from the position seen in FIG. 4 to the position seen inFIG. 2, so placing the suction cleaner fan in communication with thespace between brushes l5.

Throughout this entire operation, it is unnecessary for the user tomanipulate the nozzle directly, all of the movements just describedbeing effected by manipulation of the wand 32 to which elbow 33 isattached.

Referring to FIGS. 2, 3 and 9, it will be noted that the arms 37 areeach of such shape and size that, when portion 36 of the combinationconnector and valve member 34 registers with passage 9, one edge of eacharm 37 engages the bottom of the corresponding slot in member 2.Similarly, when portion 36 registers with passage 13, the other edge ofeach arm 37 engages the bottom of the corresponding slot in member 3.Accordingly, when the combination connector and movable valve member 34is in either of its two extreme pivoted positions, one arm 37 is heldbetween detent member 49 and the bottom of the corresponding slot 24,25. Since detent-carnming surfaces are provided on each supporting arm,it is not necessary that, during assembly of the nozzle, a particularone of the supporting arms be disposed in particular ones of the slots.

While work-engaging elements it) have been illustrated as including anadjustable comb member of known construction, it is to be understoodthat such elements can take any form suitable for use in cleaning aparticular type of surface, such as rug R. Similarly, the particularconfiguration and disposition of brushes 15 is not critical to theinvention,

What is claimed is:

1. In a multi-purpose suction cleaner nozzle, the combination of anozzle body having a pair of separate and independent,oppositelydisposied work faces and means defining a pair ofsubstantially L-shaped air passages one arm of each communicating with adifferent one of said work faces, and the other arm ofeach terminatingin an outlet opening, said outlet openings beingseparated but lyingadjacent each other, and the edges of said outlet openings all definingan arcuate surface; a hollow connector adapted for connection to an airconducting conduit and having an air inlet opening, the edges of saidinlet opening defining a curved surface identical with the curvedsurface defined by the edges of said outlet openings, one of saidsurfaces being concave and the other convex; and means mounting saidconnector on said nozzle body for pivotal movement about an axis locatedat the center of said arcuate surfaces, so that, as said connector ispivoted, said inlet opening is brought selectively into alignment withsaid outlet openings.

2. In a multi-purpose suction cleaner nozzle, the combination of twobody members each having a work face and an opposite face, said oppositefaces being adapted to mate with each other, each body member having anair passage communicating with the work face of such body member, saidair passages having outlet openings which are adjacent when said matingopposite faces are engaged with each other, each of said body membersbeing provided with a pair of open slots disposed one on each side ofbut separated from the air passage in such body memher; a hollowconnector adapted for connection to an air conducting conduit and havingan air inlet opening of such size and shape as to be registrable witheither of said outlet openings to place the interior of said connectorin communication with the air passage leading to such outlet opening;means securing said body members together with said mating oppositefaces in contact and with said pairs of open slots registering with eachother to provide a pair of spaces; and means pivotally mounting saidconnector on said body members for movement to bring said inlet openingselectively into registry with said outlet openings, said meanscomprising two supporting arms each extending through a different one ofsaid pair of spaces. Y

3. In a multi-purpose suction cleaner nozzle, the combination of a bodymember having two work faces and two internal air passages each leadingto a different one of said work faces and each having an outlet openingdirected rearwardly of the body; a hollow connector adapted forconnection to an air conducting conduit and having an inlet openingadapted to register with either of said outlet openings; and mountingmeans supporting said connector on said body for movement to bring saidconnector selectively into registration with said outlet openings, saidbody being provided with spaces located one at each side of outseparated from said passages and opening through the rear of said bodyadjacent said outlet openings, said mountlng means including a pair ofsupport members disposed each in one of said spaces, and said inletopening being disposed between said support members.

4. Ina multi-purpose suction cleaner nozzle, the combination of two bodymembers each having a work face and an opposite face, said oppositefaces being adapted to mate with each other, each body member having anair passage communicating with the work face of such body member, saidair passages having outlet openings which are adjacent when said matingopposite faces are engaged with each other, each of said body membersbeing provided with a pair of open slots disposed one on each side ofbut separated from the air passage in such body member; a hollowconnector adapted for connection to an air conducting conduit and havingan air inlet opening of such size and shape as to be registrable witheither of said outlet openings to place the interior of said .connectorin communication with the air passage leading to such outlet opening;means securing said body members together with said mating oppositefaces in contact and with said pairsof open slots registering with eachother to provide a pair of spaces; and means pivotally mounting saidconnector on said body members for move ment to bring said inlet openingselectively into registry with said outletopenings, said meanscomprising ashaft clamped between the mating opposite faces of said bodymembers at a point adjacent the front edge thereof, and a pair ofsupporting arms'rigid with said connector and journaled on said shaft,each of said arms extending through a different one of said pair ofspaces.

5. In a multipurpose suction cleaner tool, a suction conduit connectorhaving an air inlet opening, a suction conduit elbow, said connectorbeing rotatable on said elbow about a first substantially horizontalaxis and said elbow having an arm extending at an angle to said firstaxis in a generally upward direction whenever the tool is being used forcleaning surfaces like floors and rugs, for example, the tool comprisingstructure providing a pair of nozzles in back-to-back relation, each ofsaid nozzles having a separate suction opening and a separate outlet,means pivotally mounting said connector on said nozzle structure forangular movement through an acute angle between two positions about asecond substantially horizontal axis which is transverse to said firstaxis, each of the suction openings being movable to a downward facingcleaning position responsive to rotation of said connector about saidfirst axis through an angle of 180 from the downward facing cleaningposition of the other of said suction openings, and means embodied insaid nozzle structure and said connector for bringing the outlet of oneof said nozzles in communication with the inlet of said connector whenthe suction inlet of said one nozzle is in a downward facing cleaningposition and said connector is moved to one of its two positions aboutsaid second axis, and for bringing the outlet of the other of saidnozzles in communication with the inlet of said connector when thesuction inlet of said other nozzle is in a downward facing cleaningposition and said connector is moved to the other of its two positionsabout said second axis.

6. In a multi-purpose suction cleaner tool, a suction conduit connectorhaving an air inlet opening, a suction conduit elbow, said connectorbeing rotatable on said elbow about a first substantially horizontalaxis and said elbow having an arm extending at an angle to said firstaxis in a generally upward direction whenever the tool is being used forcleaning surfaces like floors and rugs, for example, the tool comprisingstructure providing a pair of nozzles in back-to-back relation, each ofsaid nozzles having a separate suction opening and a separate outlet,means pivotally mounting said connector on said nozzle structure forangular movement through an acute angle between two positions about asecond substantially horizontal axis which is substantiallyperpendicular to said first axis, each of the suction openings beingmovable to a downward facing cleaning position responsive to rotation ofsaid connector about said first axis through an angle of 180 from thedownward facing cleaning position of the other of said suction openings,and means embodied in said nozzle structure and said connector forbringing the outlet of one of said nozzles in communication with theinlet of said connector when the suction inlet of said one nozzle is ina downward facing cleaning position and said connector is moved downwardto one of its two positions about said second axis and for bringing theoutlet of the other of said nozzles in communication with the inlet ofsaid connector when the suction inlet of said other nozzle is in adownward facing cleaning position and said connector is moved downwardto the other of its two positions about said second axis.

7. In a multi-purpose suction cleaner tool having front and rear walls,a suction conduit connector having an air inlet opening, a suctionconduit elbow, said connector being rotatable on said elbow about afirst substantially horizontal axis and said elbow having an armextending at an angle to said first axis in a generally upward directionfrom the rear wall of the tool whenever the tool is being used forcleaning surfaces like floors and rugs, for example, the tool comprisingstructure providing a pair of nozzles in back-to-back relation, each ofsaid nozzles having a separate suction opening and a separate outlet,means pivotally mounting said connector on said nozzle structure forangular movement through an acute angle between two positions about asecond substantially horizontal axis which is nearer to the front wallthan to the rear wall of the tool and substantially perpendicular tosaid first axis, each of the suction openings being movable to adownward facing cleaning position responsive to rotation of saidconnector about said first axis through an angle of from the downwardfacing cleaning position of the other of said suction openings, andmeans embodied in said nozzle structure and said connector for bringingthe outlet of one of said nozzles in communication with the inlet ofsaid connector when the suction inlet of said one nozzle is in adownward facing cleaning position and said connector is moved downwardto one of its two positions about said second axis and for bringing theoutlet of the other of said nozzles in communication with the inlet ofsaid connector when the suction inlet of said other nozzle is in adownward facing cleaning position and said connector is moved downwardto the other of its two positions about said second axis.

8. In a multi-purpose suction cleaner tool, a suction conduit connectorhaving an air inlet opening, a suction conduit elbow, said connectorbeing rotatable on said elbow about a first substantially horizontalaxis and said elbow having an arm extending at an angle to said firstaxis in a generally upward direction whenever the tool is being used forcleaning surfaces like floors and rugs, for example, the tool comprisingstructure providing a pair of nozzles in back-to-back relation, each ofsaid nozzles having a separate suction opening and a separate outlet,means pivotally mounting said connector on said nozzle structure forangular movement through an acute angle between two positions about asecond substantially horizontal axis which is substantiallyperpendicular to said first axis, each of the suction openings beingmovable to a downward facing cleaning position responsive to rotation ofsaid connector about said first axis through an angle of 180 from thedownward facing cleaning position of the other of said suction openings,the separate outlets of said nozzles being adjacent to one another andseparated by a wall of said nozzle structure, said outlets being ofarcuate shape and having a radius of curvature about an axissubstantially coinciding with said second axis, the air inlet opening ofsaid connector being of armate shape and having a radius of curvatureabout an axis substantially coinciding with said second axis, and meansembodied in said nozzle structure and said connector for bringing theoutlet of one of said nozzles into registry with the inlet of saidconnector when the suction inlet of said one nozzle is in a downwardfacing cleaning position and said connector is angularly moved downwardto one of its two positions about said second axis and for bringing theoutlet of the other of said nozzles into registry with the inlet of saidconnector when the suction inlet of said other nozzle is in a downwardfacing cleaning position and said connector is angularly moved downwardto the other of its two positions about said second axis.

References Cited in the file of this patent UNITED STATES PATENTS2,212,942 Karlstrom Aug. 27, 1940 2,278,096 Ross Mar. 31, 1942 2,319,927Hansson May 25, 1943 2,516,205 Hallock July 25, 1950 2,624,064 SnyderJan. 6, 1953 2,632,914 .White Mar. 31, 1953 2,885,716 Brown May 12, 19592,885,717 Lampe May 12, 1959

